Designing a high-efficiency ejector requires a precise balance of thermodynamics and fluid mechanics. Using an Excel-based calculation tool (XLS) allows engineers to quickly iterate through design variables like nozzle geometry and pressure ratios. Understanding Ejector Design Calculations
The diffuser converts velocity back to pressure. Diffuser efficiency (η_diff) is typically 70–85%.
To design an ejector calculation spreadsheet, you must model the three primary components: the motive nozzle, the suction/mixing chamber, and the diffuser. The core goal is to determine the Entrainment Ratio ( )—the ratio of entrained vapor to motive steam mass flow. 1. Key Design Inputs ejector design calculation xls
Case study from literature: Steam ejector (El-Dessouky et al., 2002)
Empirical Correlations: Using constants (A through J) to determine performance based on expansion and compression ratios. Nozzle : A converging nozzle where the high-velocity
Ejectors (also known as jet pumps or eductors) are simple yet highly effective devices that use a high-pressure fluid (motive fluid) to entrain and compress a lower-pressure fluid (suction fluid). They are widely used in chemical plants, HVAC systems, vacuum distillation, and wastewater treatment.
$$V_m = M_m \times \sqrtk \cdot R \cdot T_m$$ Mastering Ejector Design Calculation Using Excel (XLS) –
: Input the constants (A-J) into a hidden table to reference in your calculation formula. Solve for Geometry : Use the area ratio formulas to output the required Nozzle Throat Diameter Mixing Section Diameter Validation Ejector Capacity Calculator or similar tools to cross-check your results. ✅ Summary of Results The design of an ejector in Excel requires solving for the Entrainment Ratio ( using pressure ratios ( ) and empirical constants, then applying Area Ratio